The objective is to obtain more accurate information relating to the very low birth weight (VLBW) infant, <1500 grams, for calendar year 1987 than is now available from the United States vital records. This objective will be accomplished by the following: (1) to design and administer a mail questionnaire to mothers of VLBW infants, mothers of all fetal deaths, and a sample of mothers of LBW infants (1,500-2,499 grams) and normal birth weight infants (greater than or equal to 2,500 grams) in order to obtain and verify information from the prenatal, perinatal, and post-neonatal periods: (2) to design and conduct telephone follow-up interviews on non-respondents and incomplete respondents, and a 10 percent sample of study mothers to obtain and/or verify information on mail questionnaires; (3) to develop and conduct procedures for ascertaining from hospital and physician records unavailable or missing information on morbidity, lifestyle, and socioeconomic indicators of the study subjects; and (4) to prepare and deliver an edited data tape to NICHD. In addition, mortality will be ascertained throughout the first year of life for this birth cohort. This information will help to answer the question: Has there been a reduction in neonatal mortality at the expense of an increase in post-neonatal mortality for these infants?